Method of weaving wire cloth



Filed May 11, 1953 W. A. KOOLS METHOD OF WEAVING WIRE CLOTH 4Sheets-Sheet l Dec. 27; 1955 w. A. KOOLS 2,728,358

METHOD OF WEAVING WIRE CLOTH Filed May 11, 1955 4 Sheets-Sheet 3 CE/VTEEFem/r V P642 Dec. 27, 1955 Filed May 11, 1953 AT- UP giAT-UP W. A. KOOLSMETHOD OF WEAVING WIRE CLOTH 4 Sheets-Sheet 4 United States Patent '0METHOD OF WEAVING WIRE CLOTH William A. Kools, Neenah, Wis. ApplicationMay 11, 1953, Serial No. 354,257

10 Claims. (Cl. 13955) This invention is concerned with the weaving ofwire cloth and is particularly directed to improving the characteristicsof the type of twill wire cloth which is intended for use as the formingwire of a Fourdrinier paper machine.

There are many considerations which enter into the selection of aparticular type and mesh of weave in a Fourdrinier wire, two of the moreimportant ones being the tendency of the wire to leave a mark upon thepaper web, and the useful life of the wire. A majority of theFourdrinier wires used today are of the twill weave, and althoughseveral types of twill have been experimented with from time to time,the one-up-two-down twill has become, for practical purposes, thestandard for twill woven wires. The wire cloth is either welded, brazedor soldered into an endless belt which is entrained around a series ofrolls in the forming section of the Fourdrinier machine, with the longcrimp or knuckle of the warp wire disposed to contact the rolls,suctionboxes, etc., of the machine. Theoretically, this places a greaterlength of the warp wires in contact with the rolls, and other conditionsbeing equal, would increase the life of a twill-woven wire over that ofthe plain weave. As a matter of actual fact, however, the methods ofweaving twill wire cloth which prevail in the industry produce in thewarp wires of the cloth an unsymmetrical or non-uniform long crimp whichis deeper at one end than at the other, and which therefore contacts therolls of the paper machine along only a small portion of its length,called the heel. In some Fourdrinier wires, this condition is improvedby rolling the wire between pressure rolls after it is woven in order toflatten the long crimp or knuckle, and thus at least partially eliminatethe heel, but this additional operation necessarily increases the costof rolled wire raising its price in the present market by about percent. Accordingly, the principal object of the invention hereinafterdescribed is to provide a method of weaving twill wire cloth which willproduce a symmetrical and uniform long crimp in the first instance,thereby increasing the life of Fourdrinier wires and reducing theirpaper-marking tendencies without increasing their cost.

It will be understood, of course, among those skilled in the art that atwill cloth may be woven with one set of warp wires raised and theremainder of the warp wires lowered, or conversely, that one set of warpwires may be lowered and the majority raised. Therefore, throughout thisspecification, when reference is made to a one up-two-down twill, or toany other type of twill, it is immaterial whether the one or more setsof warp wires which are separated from the majority to form the shed,are raised or lowered. For the sake of convenience, however, the methodof the invention will be described in connection with the moreconventional practice of forming the shed by raising one set of warpwires above the remaining warp wires, and by reference to aone-up-twodown twill weave, which is the twill weave most commonly usedfor Fourdrinier wires.

Briefly, the method of the invention contemplates a regulation of therelative tensions of the lower warp wires, i. e., those which are beingformed into the long crimp, during the beat-up of the shute wire intothe fell of the cloth. It has been discovered that if, during thebeat-up of the shute wire, a greater tension is maintained in that setof lower warp wires which formed the top of the shed for the insertionof the next previous shute wire, than in the remaining lower warp wires,the' heel which occurs in the long crimp of twill cloth woven inaccordance with prevailing practice, can be eliminated, and asymmetrical, uniform bottom crimp or knuckle produced.

The invention will be better understood by reference to the accompanyingdrawings in which there is illustrated one form of loom mechanismadapted for carrying out the method of the invention.

In the drawings:

Figure l is a more or less diagrammatic sectional representation of anundercam wire loom showing, for the sake of clarity, only those portionswhich are essential in arriving at an understanding of the invention;

Figures 2A to 2F are line diagrams indicating the relative positions ofthe warp wires during one cycle or round in the weaving of aone-up-two-down twill wire cloth in accordance with the invention;

Figures 3A to 3F are similar line diagrams illustrating the positions ofthe warp wires during one cycle of weaving by a modified form of themethod indicated by Figure 2;

Figure 4 is'a diagrammatic illustration of the outlines of the harnesscams of an undercam loom for achieving the shedding motions representedby Figure 2;

Figure 5 is a similar diagram showing the outline of a single cam forachieving the shedding motions illustrated in Figure 3, only one of aset of three similarly shaped earns being shown;

Figure 6 is a magnified longitudinal cross-section of a short segment oftwill wire cloth woven by the prevailing methods and illustrating theunsymmetrical long crimp of the warp wire; and

Figure 7 is a similar cross section of a segment of twill wire clothproduced in accordance with the method of the invention.

It is understood among those skilled in the art, that other variablefactors remaining constant, the tension of the warp wires is determinedby the amount by which the warp wires are moved away from the warp linein the formation of the shed, the greater the movement of the heddleframes or harnesses from their respective positions at which the warpwires lie in the warp line, the greater the resulting tension in thewarp wires. In the specific illustrations to follow, it is thereforeproposed to achieve the regulation of warp tension which underlies themethod of the invention, by providing a differential shedding motion inwhich the bottom line of the shed, or bottom shed, as it is commonlycalled, is split after the loom has picked, so as to maintain adifference in tension between certain of the several sets of lower warpwires during the beat-up on the shute wire. It is recognized, however,that the requisite tension differential may be achieved in other ways,and the systems of shedding hereinafter specifically described aretherefore to be considered as illustrative, rather than as limiting, ofthe invention.

Referring now to the drawings, the loom illustrated in Figure l is of aundercam type in which each of the heddle frames or harnesses ispositioned independently of the others by means of a cam-actuatedtreadle operating against the force of a spring which tends to raise theheddle frame.

The loom comprises a pair of side frames 10 connected together by upperand lower tie beams 12 and 14 and providing journals for a warp beam 16,a breast r011 18 and a cloth roll 20. In the loom shown in Figure l, theweaving action takes place from right to left, the warp wires 22 leavingthe warp beam, passing through the heddle frames 24 and the reed 26, thecloth 28 being taken up by the breast roll and passed to the cloth roll.The three heddle frames shown are suspended by means of rods or thelike, from springs 30 mounted on a plate 32 supported from the sideframes 10, and the lower ends of the heddle frames being connected bycables or the like to individual treadles 34, each of which is pivotallymounted on the lower tie beam 14. The cam shaft 36 is disposed aboutmid-way along the length of the treadles, the follower 33 of eachtreadle being urged against the periphery of its associated cam 40 bythe heddle spring. As the cam shaft rotates, each harness is alternatelydepressed and elevated by its associated cam and heddle springrespectively, following the path of movement determined by the outlineof the cam. While the extent of the heddle motion is normally determined completely by the throw of its cam, there is also provided foreach heddle frame a stop screw 42 against which the upper end of theheddle frame may abut to determine the upper limit of its travel.

The lay 44, shown in the beat-up position in Figure 1, is suspended fromthe tops of the side frames by a knife edge 46 or other suitable pivot.It consists of the usual side arms or swords 48 connected by the laybeam 50 which provides support, in a manner not shown in detail, for thereed 26. Extending forwardly from the beam of the lay is a shuttle race52 on which the lower warp wires lie when the loom picks. It will beapparent from Figure 1 that when the lay 44 is drawn rearwardly for thepassage of the shuttle, it is elevated somewhat above its position atthe beat-up.

One sequence of heddle motions for accomplishing the desiredrelationship of tensions in the lower sets of warp wires in the weavingof a one-up-two-down twill in accordance with the invention is showndiagrammatically in Figure 2. In this case, the shed is formed byraising one of the three sets of warp wires above the warp line andmaintaining the two remaining sets depressed below the warp line insubstantially co-plauar relationship for the passage of the shuttle.Then, after the loom picks and before the shute wire is beat-up into thefell of the cloth, one of the lower sets of warp wires is elevated so asto relieve its tension, while maintaining the other set in the fullydepressed position so as to maintain a higher tension in the lower oneof the two bottom sets of Wires.

In each case, the set of lower warp wires in which the higher tension ismaintained is the set which formed the top of the shed during thebeat-up of the previous shute wire. This sequence of shedding motionstherefore results in six different positions of the Warp wires in theweaving of a one-up-two-down twill, these positions being indicated bythe diagrams A through F inclusive of Figure 2.

In Figure 2A, the three sets of Warp wires 54, 56 and 58, associatedrespectively with the front, center, and rear heddle frames, arearranged for the beat-up of the first shute wire of the round orsequence. The front heddle is fully raised, the rear heddle is fullydepressed, and the center heddle occupies an intermediate position. Inthis case, therefore, the warp wires associated with the rear heddleframe are tensioned to a greater extent than those associated with thecenter heddle.

In Figure 2B, the warp wires are disposed for the next succeeding pickof the loom. In this case, the warp wires 56 associated with the centerheddle form the top of the shed, and the warp wires 54 and 58 associatedwith the front and rear heddles constitute the bottom of the shed, thelatter two sets of wires being co-planar and in contact with the shuttlerace 52 for the passage of the shuttle. After the loom picks, the threesets of warp wires are moved to the position indicated in Figure 2C.

It will be noted that the position of the wires in Figure 2C differsfrom that of Figure 2B only in that the warp wires 58 associated withthe rear heddle are raised slightly so as to relieve their tension,while maintaining the tension in the warp wires 54 associated with thefront heddle, and this is the position which the warp wires assume forthe beat-up of the second shute wire of the round. After the beat-up ofthe second shute wire, the warp wires are moved to the positions ofFigure 2D for the next pick.

in Figure 2D, the warp wires 53 associated with the rear heddle now formthe top of the shed and those associated with the front and intermediateheddles constitute the bottom of the shed for the passage of theshuttle. After the loom picks, the warp wires are then disposed asindicated in Figure 2B for the beat-up of the third shute wire of theround. Again it will be noted that the disposition of Figure 2E differsfrom that of Figure 2D only in that the warp wires 54 associated withthe front heddle have been raised so as to relieve their tension ascompared with the tension that is maintained in the warp wires 56associated with the intermediate heddle.

After the beat-up of the third and final shute wire of the round, theheddles are moved from the position of Figure 213 to the position ofFigure 2F for the insertion of a shute wire to start a new round,following which the sequence of positions 2A to 2F is repeated.

From the foregoing, it will be noted that each of the heddle frames inturn passes from the fully raised position to the fully depressedposition, and thence to an intermediate position at which the tension inthe warp wires associated with the heddle frame is relaxed as comparedwith the other warp wires, particularly the other lower set. In eachcase, the set of lower warp wires in which the greater tension ismaintained is the set which formed the top of the shed during thebeat-up of the previous shute wire.

A system of three cams for achieving the foregoing shedding motions inthe undercam loom arrangement of Figure 1 is shown diagrammatically inFigure 4. There it will be noted that the three cams 66, 62 and 64 aresimilar in outline, but that the cams are displaced degrees from eachother on the cam shaft, and that the throw of the cams increasesprogressively from the cam 63, associated with the front harness, to thecam 64, associated with the rear harness, as is customary. Each of thecams comprises a minor-radius dwell portion 66, corresponding with theraised position of its associated heddle, and which in the illustratedcams, occupies a 90 degree segment of the cam outline. Then,proceedingin a direction opposite to the indicated direction of the rotation ofthe cams, the next 30 degree segment 68 of the cam outline moves thetreadle downwardly to its fully depressed position, bringing the warpwires associated therewith down On to the shuttle race. The greaterradius dwell 70, which corresponds to the fully depressed position ofthe heddle frame, occupies a degree segment of the cam outline, and isfollowed immediately by another dwell '72 of approximately 60 degreesduration which corresponds to the intermediate position of the heddle.In the next and final 30 degree segment 74 of the cam outline, theheddle is raised again to the upper position.

As indicated by the cam diagram of Figure 4, the change of the heddleframes from the fully raised position to the fully lowered positiontakes place in a rotation of the cam shaft of 38 degrees; a space of 30degrees is allotted for the picking of the loom, and this is followed byan allotment of 60 degrees for the beat-up, this sequence occurringthree times in each cycle of weaving a one-up-two-down twill. It will beunderstood by those skilled in the art, however, that these allotmentsmust necessarily vary from loom to loom and are dependent upon the widthof the loom, its speed,

and other factors. The arrangement of Figure 4 therefore is intendedprimarily for the purpose of illustration.

A modified shedding arrangement for achieving the same overall result isillustrated in Figures 3 and 5, in connection with the weaving of aone-up-two-down twill. In this case, as before, the shed is formed byraising one of the several sets of warp wires, while maintaining theremaining sets in a depressed position to constitute the bottom of theshed for the passage of the shuttle. However, after the shuttle ispassed, and as the lay moves forward to beat the shute wire in the fellof the cloth, one of the lower sets of warp wires is depressed stillfarther while the other set, or sets if there be more than one, areraised above the position which they occupied when the loom picked. Inthis manner, as with the system of shedding of Figures 2 and 4, agreater tension is maintained in the lower set of warp wires of thesplit bottom shed, but the tension differential which can be achieved isgreater than before, other variable factors remaining constant. In thiscase, however, it is essential that the splitting of the bottom of theshed take place after the lay begins its forward motion in order toprovide the necessary clearance for the further depression of the lowerwires of the split bottom shed.

Referring to Figures 3A to 3F inclusive, which show the six dispositionsof the three sets of warp wires during a single cycle or round ofweaving a one-up-twodown twill with the modified shedding arrangement,Figure 3A represents the positions of the three sets of warp wires 75,77, and 79 at the beat-up of the first shute wire of the round. Thefront heddle is raised, the rear heddle is fully depressed, and thecenter heddle occupies an intermediate position slightly below the warpline.

In Figure 2B, the three sets of warp wires are arranged for the nextpick of the loom, the warp wire 77 associated with the center heddlebeing fully raised, and the wires 75 and 79 associated with the frontand rear heddles being depressed, substantially co-planar, and lying onthe shuttle race 52.

Figure 3C shows the position of the three sets of warp wires for thebeat-up of the second shute wire of the round. The bottom of the shed isagain split, the wires 75 associated with the front heddle beingslightly depressed, the wires 79 associated with the rear heddle beingslightly raised from the positions which they occupied in Figure 3B.

In Figure 3D, the three sets of warp wires are arranged for the thirdand last pick of the sequence, the

wires 79 associated with the rear heddle being fully raised, and thefront and center heddles being lowered with their associated wires 75and 77 lying on the shuttle race 52.

In Figure 3E, the three sets of wires are arranged for the beat-up ofthe last shute wire of the round, this disposition of the warp wiresdiffering from that of Figure 3D, only in that the front heddle has beenraised to position its associated warp wires 75 closer to the warp line,and the intermediate heddle has been further depressed to position itsassociated wires 77 farther away than before from the warp line.

Figure 3F shows the disposition of the warp wires for the insertion ofthe first shute wire of the next sequence or round.

In each case, as with the shedding arrangement of Figures 2 and 4, eachheddle frame, at the beat-up of successive shute wires, occupies inorder the fully raised position, the fully depressed position, and thenthe intermediate position, so that the set of lower warp wires in whichthe greatest tension is maintained during the beat-up is the set whichformed the top of the shed during the beat-up of the previous shutewire.

The cam outline for achieving the shedding motions of Figure 3 is showndiagrammatically in Figure 5.

In this case, the outline of only one of the cams is shown, but it willbe understood as before that three cams, each rotated 120 degrees fromthe other, are provided, and that the throw of the cams increasesprogressively from that associated with the front heddle to thatassociated with the rear heddle.

The difference between the results of the method of the invention andthe results of the prevailing methods, will be apparent from Figures 6and 7. Figure 6 shows the conformation of a warp wire 81 in a segment ofone-up-two-down twill wire cloth woven by the prevailing methods. Itwill be apparent that the long hottom crimp or knuckle 83 is uneven,having a deeper and sharper bend or heel 85 in the first or leadingportion of the knuckle, i. e., the bend which is formed by the beat-upof the first shute wire 87 under which the warp wire passes. On thebeat-up of the succeeding shute wire 89, the brunt of the force ofbeating up the shute wire is borne by the adjacent warp wires, with theresult that the final bend 91 of the lower crimp 83 is less pronounced.It will be apparent that insofar as Fourdrinier wire is concerned, thecapabilities of the twill weave for greater wire life cannot be fullyrealized with the twill wires woven by prevailing methods, withoutsubsequent treatment, because the wear on the long crimp 83 cannot beevenly distributed. Furthermore, the short top crimp 93, as well as thecrimping of the shute wires, is more pronounced, with the result thatthere is a greater tendency toward marking of the paper web than is thecase with a Fourdrinier wire woven in accordance with the presentinvention, shown in Figure 7. In the latter, it will be noted that thelong bottom crimp 95 of the warp wire 97 is symmetrical and parallelwith the plane of the cloth, there being no heel, as in the case withthe conventional twill wire. Other factors being equal, therefore, thelife of a Fourdrinier wire woven in accordance with the method of theinvention may be increased substantially over the conventional wire andwill, as a corollary of the uniform bottom crimp, exhibit a lessertendency to mark the paper web.

While the invention has been described in connection with the weaving ofa one-up-two-down twill wire cloth, which is the commonly used twillweave for Fourdrinier wires, it is believed to be equally applicable toother types of twills, the essence of the invention being themaintenance of a greater tension, during the beat-up of the shute wire,in that set of warp wires which form the top of the shed during thebeat-up of the previous shute wire.

The features of the invention believed to be new and patentable are setforth in the appended claims.

I claim:

1. In the weaving of twill wire cloth with a plurality of interspersedsets of warp wires each set of which is successively separated from theother sets to form a shed for the insertion of a shute wire, theimprovement which comprises maintaining a greater tension in one of saidother sets of warp wires than in the remainder of said other sets duringthe beat-up of the shute wire, said one set being the set which occupiedthe separated position for the insertion of the previous shute wire.

2. In the weaving of twill wire cloth with a plurality of interspersedsets of warp wires on a loom having an equivalent number of heddles eachof which is separated in turn from the remaining heddles to form a shedfor the insertion of a shute wire, the improvement which comprises thepositioning of one of said remaining heddles more remote from theseparated heddle than the others of said remaining heddles during thebeat-up of the shute wire thereby to maintain in the warp wiresassociated with said one heddle a greater tension than in the warp wiresassociated with the others of said remaining heddles, said one heddlebeing the one which occupied the separated position for the insertion ofthe previous shute wire.

3. In the weaving of twill wire cloth with a plurality of interspersedsets of warp wires on a loom having an equivalent number of heddles eachassociated with one of said sets and each of which is separated in turnfrom the remaining heddles to form a shed for the insertion of a shutewire, the improvement which comprises the positioning of all but one ofsaid remaining heddles closer to the separated heddle than said oneheddle during the beat-up of the shute wire, thereby to maintain agreater tension in the warp wires associated withrsaid one heddle thanin the warp wires associated with the others of said remaining heddles,said one heddle being the one which occupied the separated positionduring the beat-up of the previous shute wire.

4. In the weaving of twill wire cloth with a plurality of interspersedsets of warp wires on a loom having an equivalent number of heddles eachassociated with one of said sets and each of which is raised in turnabove the remaining heddles to form a shed for the insertion of a shutewire, said remaining heddles being positioned relative to one another soas to align their associated warp wires in a substantially common planeduring the passage of the shuttle through the shed, the improvementwhich comprises raising all but one of said remaining heddles after theinsertion of the shute wire and during the beat-up without closing theshed, thereby to maintain in the warp wires associated with said oneheddle a greater tension than in the remainder of the lower warp wiresduring the beat-up of the shute wire into the fell of the cloth, saidone heddle being the one which was raised to form the shed for theinsertion of the previous shute wire.

5. In the weaving of twill wire cloth with a plurality of interspersedsets of warp wires on a loom having an equivalent number of heddles eachassociated with one of said sets and each of which is raised in turnabove the remaining heddles to form a shed for the insertion of a shutewire, said remaining heddles being positioned relative to one another soas to align their associated warp wires in a substantially common planeduring the passage of the shuttle through the shed, the improvementwhich comprises depressing one of said remaining heddles and elevatingthe others of said remaining heddles after the insertion of the shutewire and during the beat-up without closing the shed, thereby toincrease the tension in the warp wires associated with said one heddleand to decrease the tension in the other lower warp wires when the shutewire is heat into the fell of the cloth, said one heddle being the onewhich was raised to form the shed for the insertion of the previousshute wire.

6. In the weaving of a one-up-two-down twill wire cloth, the improvementwhich comprises splitting the bottom of the shed for the beat-up of theshute wire, thereby to maintain a higher tension in the lower warp wiresof said shed bottom than in the upper wires of said shed bottom, thelower set of bottom warp Wires being those.

which formed the top of the shed for the insertion of the previous shutewire.

7. In the weaving of a one-up-two-down twill wire cloth, the improvementwhich comprises splitting the bottom of the shed after the insertion ofthe shute wire and before the beat-up by elevating one of the bottomsets of warp wires thereby to maintain a greater tension in the lowerwarp wires of said shed bottom than in the upper wires of said shedbottom during the beat-up, the said lower warp wires being those whichformed the top of the shed for the insertion of the previous shute wire.

8. In the weaving of a one-up-two-down twill wire cloth, the improvementwhich comprises splitting the bottom of the shed during the beat-up bydepressing one of the sets of bottom warp wires while raising the otherset thereby to maintain a greater tension in the lower warp wire of saidshed bottom than in the upper warp wires of said shed bottom when theshute wire is heat into the tell of the cloth, said lower warp wiresbeing those which formed the top of the shed for the insertion of theprevious shute wire.

9. In the weaving of twill wire cloth with a plurality of interspersedsets of warp wires each set of which is successively separated from theother sets to form a shed for the insertion of a shute wire, theimprovement which comprises increasing the tension in one of said othersets of warp wires and reducing the tension in the remainder of saidother sets of warp wires for the beatup of the shute wire, said one setbeing the set which occupied the separated position for the insertion ofthe previous shute wire.

10. An improved method of shedding in the weaving of twill wire cloth ona loom, which comprises moving each heddle in turn from an intermediateposition on one side of the warp line to an isolated position on theother side of the warp line and thence to a position on said one side ofthe warp line more remote from said warp line than said intermediateposition thereby to effect a greater tension in the warp wires at saidlast mentioned position than at said intermediate position, and thenceback to said intermediate position, the shute wire being inserted in theshed formed between the warp wires of the heddle in said isolatedposition and the warp wires of the heddles in the other of saidpositions, one of said heddles being in its isolated position, anotherbeing in said last mentioned position and the remainder of the heddlesoccupying their intermediate positions when the shute wire is beat-upinto the fell of the cloth.

References Cited in the file of this patent FOREIGN PATENTS,

404,344 Germany Oct. 16, 1924

